Eccentric lifting device



f H. BREITWIESER ECCENTRIC LIFTING DEVICE Filed May 18, 1931 Jan. 3, 1933.

Patented Jan. 3, 1933 UNETED STATES PATENT OF F ICE.v

HEINRICH BREITWIESER, OF GRIESHEIM NEAR DAR-MSTADT, GERMANY, ASSIGNOR.

TO MASCHINENFABRIK AUGSBURG-NURNBERG, A. G., OF NUREMB-EBG, GERMANY, A L

conronerron or GERMANY ECCENTRIC LIFTING DEVICE Application filed May 18, 1931, Serial No.

This invention relates to an eccentric lifting device, especially for use in connection with the ends of pivot bridges. It is an improvement of such devices of the type illustrated in U. S. Patent No. 1,807,780 in which two eccentric disks are movable along horizontal path and act as bearings for a supporting roller arranged between them, which roller moves upwardly upon rotation of said discs during the power stroke of actuating means for the device and takes up the load. The general object of this improvement is to relieve the lifting device, particularlythe eccentric and lifting disks thereof,of load while the bridge is in operative position, in a more advantageous manner than hitherto.

According to the construction disclosed by the aforesaid patent the relief is effected by lowering the lifting disk a little from its highest position so as to place it down upon a supporting member arranged between the running paths, and by lifting the running disks off their running paths so that the entire load rests upon said supporting member.

It has, however, been found that, owing to the elastic changes of the shape in the ma terial when the lifting disks are seated upon the supporting member, the operation of the gear is accompanied by strong frictional resistances which entail detrimental efiects in the course of time. More particularly, therefore, the object of the present invention is to obviate the detrimental effects, mentioned by the provision of a supporting member which is separate from the lifting disk and which, in the normal position of the bridge end, supports the load thereof and thereby relieves the remaining parts of the device of load. I attain this object by the provision of a supporting member which is movably supported by and extends below the lifting disk and is urged by a spring against the front wall of a downwardly widening slot, in the lifting disk so that upon movement of the lifting disk in a direction to lift the bridge end and upon engagement of the lower end of the sup porting member with a suitable stop, continued movement of the lifting disk with the running disks, permitted by the downwardly 538,061, and in Germany May 21', 1930'.

widening slot, results in theload being trans.- M

suitable bearing when it has seated down thereon. so that on the continued movement of the lifting disk and when the running disks are lifted no friction whatever of theparts subjected to the load of the bridge arises.

The invention is illustrated diagrammatically and by way of example on the accompanying drawing on which Figure 1 is a sideview, partly in vertical section, of the lifting. device, Figure 2 is a plan of the eccentric mechanism. Figure 3 is a frontal, view of this mechanism, seen from the lefthand disk with its slot. And Figs. 4-7, are vertical sections through the lifting disk with its slot, and of some adjacent members, together with side-views of the supporting member located in said slot, these parts being shownin several positions, all as more fully described hereinafter.

At a are shown two circular running disks having eccentrically arranged circular bores provided with suitable bearings 72 through which pass the trunnions 0 of a lifting disk cl disposed between said running disks. Pins 79 disposed in bearing eyes 9 of the running disks 4; are engaged by thrust rods 7 connected with a suitable driving device as illustrated, for example, in the aforementioned U. S. Patent 1,807,780, and by means of said rods the running disks may be caused to roll in one direction or the other over tracks or paths 6 which are slightly inclined downwardly towards the driving device. On the inner faces of the disks a are rims a." for guiding said disks on the tracks 6, While toothed sectors a" on said disks mesh with racks s on the tracks 6 to positively assure movement of the disks along the tracks when the disks are rotated. r

The lifting disk (Z is provided a practically vertical slot f'that is downwardly enlarged,

as shown in Figs. 4-7. In this slot is arranged a supporting member g, which, near its lowerlend, carries lateral rollers h (Figs. 1-3) bearing upon ledges i aflixed to the disk at. Connected to the supporting member 9 bination of these parts appear particularly distinct from Fig. 1. The two lever arms V Z are connected with one another by a trans-x verse member Z, which is subjected tothe pressure of a helical spring m which is preferabl-y guided by a bolt extending forth from said transverse member Z, as shown in Fig. 1. r The other end of the spring bears upon theliftingdisk d. Owing tothe arrangementfand combination of these parts the spring m tends continually to draw the: supporting member 9 towards the lefthand (with respect to Figs. 1- and 4&7) wall of the slot f, as well as to turn the disk d in the opposite' direct-ion. The arrows in Figs. 4 7 indicate .the direction of action of the spring with respect to the member Betweenthe running members 6 is located a, stationary block at provided with an abutment 0 which when the lifting disk 0 is moved upwardly is located in the path of the lower end of the supporting member 9 which projects forth from the lower end of the slot 7. In this position of; these parts the upper end of-the member 9 lies flush with the upper end, of said slot." 1

' .IVhen the rolls a, a, are moved from the right to the left, the supporting member 9 is first moved downwardly so as to contact with f the block a, and then to the left as indicated by the above-mentioned arrows) so that its end contacts with the abutment o, as in Fig. 5. ,If, when the parts arein this position, the disks a and '(Z are further turned, the disk d will be lowered, as will be also the supporting member c ,'and this latter will then bear upon the5block n, as in Fig. 6. The disk (Z proceeds, however, in its rotary motion under the action of the spring m also as in Fig. 6, and 'when now the after-movement of the gearing takes place, the disk d is drawn off from the bridge, as in Fig. 7, the 'righthand side of the slot f contacting now with the member 9; Thus, the member 9 transmits the entire traffic load upon the block it, or upon the foundation respectively, whereas I HEINRICH BREITWI SER.

ion

the lifting mechanismis relieved therefrom. V

gIclaimz p An eccentric lifting device, especially for use in connection withthe ends of pivot bridges, comprising, in combination a lift- 7 ing disk having a practicallyvertical slot increasing in width from above to below; a supporting member extending through said 

